1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * $Id: nfs_bio.c,v 1.1 94/10/20 10:57:29 root Exp $ 37 */ 38 39 #include "sys/param.h" 40 #include "sys/file.h" 41 #include "sys/mount.h" 42 #include "uio.h" 43 #include "ucred.h" 44 #include "sys/time.h" 45 #include "sys/errno.h" 46 #include "buf.h" 47 48 #include "namei.h" 49 #include "vnode.h" 50 #include "nfs_node.h" 51 #include "nfs_v2.h" 52 #include "nfs.h" 53 #include "nfs_iom.h" 54 #include "nfs_mount.h" 55 #include "prototypes.h" 56 57 /* True and false, how exciting */ 58 #define TRUE 1 59 #define FALSE 0 60 61 /* 62 * Vnode op for read using bio 63 * Any similarity to readip() is purely coincidental 64 */ 65 nfs_bioread(vp, uio, ioflag, cred) 66 register struct vnode *vp; 67 register struct uio *uio; 68 int ioflag; 69 struct ucred *cred; 70 { 71 register struct nfsnode *np = VTONFS(vp); 72 register int biosize; 73 struct buf *bp; 74 struct vattr vattr; 75 daddr_t lbn, bn, rablock; 76 int diff, error = 0; 77 long n, on; 78 79 #ifdef lint 80 ioflag = ioflag; 81 #endif /* lint */ 82 #ifdef DIAGNOSTIC 83 if (uio->uio_rw != UIO_READ) 84 panic("nfs_read mode"); 85 #endif 86 if (uio->uio_resid == 0) 87 return (0); 88 if (uio->uio_offset < 0 && vp->v_type != VDIR) 89 return (EINVAL); 90 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 91 /* 92 * If the file's modify time on the server has changed since the 93 * last read rpc or you have written to the file, 94 * you may have lost data cache consistency with the 95 * server, so flush all of the file's data out of the cache. 96 * Then force a getattr rpc to ensure that you have up to date 97 * attributes. 98 * NB: This implies that cache data can be read when up to 99 * NFS_ATTRTIMEO seconds out of date. If you find that you need current 100 * attributes this could be forced by setting n_attrstamp to 0 before 101 * the nfs_dogetattr() call. 102 */ 103 if (vp->v_type != VLNK) { 104 if (np->n_flag & NMODIFIED) { 105 np->n_flag &= ~NMODIFIED; 106 vinvalbuf(vp, TRUE); 107 np->n_attrstamp = 0; 108 np->n_direofoffset = 0; 109 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 110 uio->uio_procp)) 111 return (error); 112 np->n_mtime = vattr.va_mtime.tv_sec; 113 } else { 114 if (error = nfs_dogetattr(vp, &vattr, cred, 1, 115 uio->uio_procp)) 116 return (error); 117 if (np->n_mtime != vattr.va_mtime.tv_sec) { 118 np->n_direofoffset = 0; 119 vinvalbuf(vp, TRUE); 120 np->n_mtime = vattr.va_mtime.tv_sec; 121 } 122 } 123 } 124 do { 125 switch (vp->v_type) { 126 case VREG: 127 nfsstats.biocache_reads++; 128 lbn = uio->uio_offset / biosize; 129 on = uio->uio_offset & (biosize-1); 130 n = min((unsigned)(biosize - on), uio->uio_resid); 131 diff = np->n_size - uio->uio_offset; 132 if (diff <= 0) 133 return (error); 134 if (diff < n) 135 n = diff; 136 bn = lbn*(biosize/DEV_BSIZE); 137 rablock = (lbn+1)*(biosize/DEV_BSIZE); 138 if (vp->v_lastr + 1 == lbn && 139 np->n_size > (rablock * DEV_BSIZE)) 140 error = breada(vp, bn, biosize, rablock, biosize, 141 cred, &bp); 142 else 143 error = bread(vp, bn, biosize, cred, &bp); 144 vp->v_lastr = lbn; 145 if (bp->b_resid) { 146 diff = (on >= (biosize-bp->b_resid)) ? 0 : 147 (biosize-bp->b_resid-on); 148 n = min(n, diff); 149 } 150 break; 151 case VLNK: 152 nfsstats.biocache_readlinks++; 153 on = 0; 154 error = bread(vp, (daddr_t)0, NFS_MAXPATHLEN, cred, &bp); 155 n = min(uio->uio_resid, NFS_MAXPATHLEN - bp->b_resid); 156 break; 157 case VDIR: 158 nfsstats.biocache_readdirs++; 159 on = 0; 160 error = bread(vp, uio->uio_offset, NFS_DIRBLKSIZ, cred, &bp); 161 n = min(uio->uio_resid, NFS_DIRBLKSIZ - bp->b_resid); 162 break; 163 }; 164 if (error) { 165 brelse(bp); 166 return (error); 167 } 168 if (n > 0) 169 error = uiomove(bp->b_un.b_addr + on, (int)n, uio); 170 switch (vp->v_type) { 171 case VREG: 172 if (n+on == biosize || uio->uio_offset == np->n_size) 173 bp->b_flags |= B_AGE; 174 break; 175 case VLNK: 176 n = 0; 177 break; 178 case VDIR: 179 uio->uio_offset = bp->b_blkno; 180 break; 181 }; 182 brelse(bp); 183 } while (error == 0 && uio->uio_resid > 0 && n != 0); 184 return (error); 185 } 186 187 /* 188 * Vnode op for write using bio 189 */ 190 nfs_write(vp, uio, ioflag, cred) 191 register struct vnode *vp; 192 register struct uio *uio; 193 int ioflag; 194 struct ucred *cred; 195 { 196 struct proc *p = uio->uio_procp; 197 register int biosize; 198 struct buf *bp; 199 struct nfsnode *np = VTONFS(vp); 200 struct vattr vattr; 201 daddr_t lbn, bn; 202 int n, on, error = 0; 203 204 #ifdef DIAGNOSTICx 205 if (uio->uio_rw != UIO_WRITE) 206 panic("nfs_write mode"); 207 if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc) 208 panic("nfs_write proc"); 209 #endif 210 if (vp->v_type != VREG) 211 return (EIO); 212 /* Should we try and do this ?? */ 213 if (ioflag & (IO_APPEND | IO_SYNC)) { 214 if (np->n_flag & NMODIFIED) { 215 np->n_flag &= ~NMODIFIED; 216 vinvalbuf(vp, TRUE); 217 } 218 if (ioflag & IO_APPEND) { 219 np->n_attrstamp = 0; 220 if (error = nfs_dogetattr(vp, &vattr, cred, 1, p)) 221 return (error); 222 uio->uio_offset = np->n_size; 223 } 224 return (nfs_writerpc(vp, uio, cred)); 225 } 226 #ifdef notdef 227 cnt = uio->uio_resid; 228 osize = np->n_size; 229 #endif 230 if (uio->uio_offset < 0) 231 return (EINVAL); 232 if (uio->uio_resid == 0) 233 return (0); 234 235 /* 236 * I use nm_rsize, not nm_wsize so that all buffer cache blocks 237 * will be the same size within a filesystem. nfs_writerpc will 238 * still use nm_wsize when sizing the rpc's. 239 */ 240 biosize = VFSTONFS(vp->v_mount)->nm_rsize; 241 np->n_flag |= NMODIFIED; 242 do { 243 nfsstats.biocache_writes++; 244 lbn = uio->uio_offset / biosize; 245 on = uio->uio_offset & (biosize-1); 246 n = min((unsigned)(biosize - on), uio->uio_resid); 247 if (uio->uio_offset+n > np->n_size) { 248 np->n_size = uio->uio_offset+n; 249 vnode_pager_setsize(vp, np->n_size); 250 } 251 bn = lbn*(biosize/DEV_BSIZE); 252 again: 253 bp = getblk(vp, bn, biosize); 254 if (bp->b_wcred == NOCRED) { 255 crhold(cred); 256 bp->b_wcred = cred; 257 } 258 if (bp->b_dirtyend > 0) { 259 /* 260 * If the new write will leave a contiguous dirty 261 * area, just update the b_dirtyoff and b_dirtyend, 262 * otherwise force a write rpc of the old dirty area. 263 */ 264 if (on <= bp->b_dirtyend && (on+n) >= bp->b_dirtyoff) { 265 bp->b_dirtyoff = min(on, bp->b_dirtyoff); 266 bp->b_dirtyend = max((on+n), bp->b_dirtyend); 267 } else { 268 bp->b_proc = p; 269 if (error = bwrite(bp)) 270 return (error); 271 goto again; 272 } 273 } else { 274 bp->b_dirtyoff = on; 275 bp->b_dirtyend = on+n; 276 } 277 if (error = uiomove(bp->b_un.b_addr + on, n, uio)) { 278 brelse(bp); 279 return (error); 280 } 281 if ((n+on) == biosize) { 282 bp->b_flags |= B_AGE; 283 bp->b_proc = (struct proc *)0; 284 bawrite(bp); 285 } else { 286 bp->b_proc = (struct proc *)0; 287 bdwrite(bp, vp); 288 } 289 } while (error == 0 && uio->uio_resid > 0 && n != 0); 290 #ifdef notdef 291 /* Should we try and do this for nfs ?? */ 292 if (error && (ioflag & IO_UNIT)) { 293 np->n_size = osize; 294 uio->uio_offset -= cnt - uio->uio_resid; 295 uio->uio_resid = cnt; 296 } 297 #endif 298 return (error); 299 } 300